If this is your first visit, be sure to
check out the FAQ by clicking the
link above. You may have to register
before you can post: click the register link above to proceed. To start viewing messages,
select the forum that you want to visit from the selection below.

ugh, frustrated

So i pulled out my 2 mags that have been sitting since last summer, put a few drops of oil in the macro line fitting and aired them up and they both leaked down the barrel but went away with a squeeze of the trigger. One is an emag valve with a level 10, I went down 1/2 of a carrier size and that one seems to be running like a champ. The other is an x-valve with level 10 and ULT, I tried to go down 1/2 a carrier size with that one and I had bolt stick issues, it would fire but would not always reset so I would have to reach down the feed tub and push the bolt back to reset it. Since I could have this I decided to go back to the original carrier with a new carrier o-ring but I have the same problem with air leaking down the barrel but going away when the trigger is pulled. I have tried removing all powertip shims as well, I just can seem to get rid of this leak.

if you removed the shims, then change the carrier. then if bolt stick, add in a shim, and try again.

I am under the impression that the carrier tightness is what causes bolt stick and that shims only determine how quickly the bolt will vent when it comes in contact with an obstruction. Is that incorrect?

I am under the impression that the carrier tightness is what causes bolt stick and that shims only determine how quickly the bolt will vent when it comes in contact with an obstruction. Is that incorrect?

that is correct...most of the big Dawgs dont even recommend using the shims...they are basically there for fine tuning.

that is correct...most of the big Dawgs dont even recommend using the shims...they are basically there for fine tuning.

Yeah, leave them out until you get it running right in other respects.

My RT did this to me last month. It had not been out in a while and had a lot of bolt stick. Part of it was that the velocity was turned down from night play, but it was also a tight fit on the o-ring. I ended up two carriers wider. Played a while; it leaked. Went down a carrier. Played a while; it leaked. Went back to the original carrier and finished up the day just fine. It seemed to be solid after that. That o-ring is probably just old and grumpy. It worked fine without paint or a barrel, so next time I'll loosen it up before trying to play.

that is correct...most of the big Dawgs dont even recommend using the shims...they are basically there for fine tuning.

At least I have correct understanding then.

Originally Posted by Spider-TW

Yeah, leave them out until you get it running right in other respects.

My RT did this to me last month. It had not been out in a while and had a lot of bolt stick. Part of it was that the velocity was turned down from night play, but it was also a tight fit on the o-ring. I ended up two carriers wider. Played a while; it leaked. Went down a carrier. Played a while; it leaked. Went back to the original carrier and finished up the day just fine. It seemed to be solid after that. That o-ring is probably just old and grumpy. It worked fine without paint or a barrel, so next time I'll loosen it up before trying to play.

My problem is I either have bolt stick or go up 1/2 carrier size and have a leak. Maybe I should just use the leaky one for a while and see if it breaks in the o-ring and then go back down to the one that is causing bolt stick and see if it remedies the problem?

1. Try changing the black oring that surrounds the carrier. These can get nicked up when sliding them past the threads in the powertube. I can usually get my valve to run with 2 or 3 different carriers without leaks. Try going up a size from the one without bolt stick that leaks. I know it sounds counterintuitive, but if the leak goes away, it may mean the smaller carrier has a bad black oring. Use the largest carrier that doesn't leak. If you need to fine tune it beyond one of the factory springs, cut a spring down, with cut side against bolt. I've always had better luck and reliability tuning via cut spring (spring constant) than fine tuning with a tighter carrier (friction dependent on lubrication).

2. Is your rail bushing present?

3. How bad is the leak? Make sure it is truly a leak and not a "seashell" effect when you have your ear up to the feedneck or barrel. I tried tuning a valve in my basement and was having intermittent barrel "leaks". Turns out I was just getting "seashell" effect when the furnace kicked on. I laughed at myself pretty good for that one.

I think i have got it worked out. The ULT seems good to me but it is the only one I have any experience with, it only has 2 shims in it. I went back to the carrier that was causing bolt stick but with a different carrier o-ring. It seems to be fine now although hitting harder than my other level 10 mag but I am also running the gold spring on this one and a longer spring on the other.

Originally Posted by athomas

How well is your ULT tuned? Try taking a shim out of it and see if it helps with the bolt stick.

I think i have got it worked out. The ULT seems good to me but it is the only one I have any experience with, it only has 2 shims in it. I went back to the carrier that was causing bolt stick but with a different carrier o-ring. It seems to be fine now although hitting harder than my other level 10 mag but I am also running the gold spring on this one and a longer spring on the other.

Two shims in the ULT shouldn't cause any issues.

You probably had a bad level 10 oring that required a carrier that was too tight in order to keep it from leaking.

The mag with the shorter gold spring will cause the bolt to hit harder than the one with the longer spring.